1. FIELD OF INVENTION
This invention relates to a system of products which are used to remove pathological or abnormal tissue from the area of the central nervous system during a surgical procedure, under direct visual control, including system components which permit establishment of a passageway into the system, creation of a space within the system if one does not normally exist where the tissue removal is to take place, illumination within the space, visualization within the space, an electromechanical cutting device which actually performs the tissue resection, a device to protect surrounding normal tissue from damage during the tissue resection, device to control bleeding if it occurs during the tissue resection, and device to transport the resected tissue from the body without having to remove visualization and tissue resecting devices from their functional position within the central nervous system, during the entire tissue removal process. This typical embodiment is an example of a system of devices which permit removal of tissue from the central nervous system under direct visual control, using any energy source, and specific accessories to make it work effectively.
2. Description of Prior Art
Normal method for surgical removal of pathological tissue from the central nervous system involves major open surgery in which a large incision is made into the scalp, which is retracted to uncover the calvarium, followed by elevation of the periosteum to expose the skull, creation of several burr holes into the skull which are then connected using a saw, and removal of a major portion of the top of the head to access the brain. The area of the brain where tissue is actually to be removed is then approached and the tissue removal occurs. Following this tissue removal, structures within the brain are placed in a relatively normal position, the top of the skull is replaced, the periosteum is sutured into its normal position, and the scalp is placed into its normal position and sutured. This open surgical procedure entails extensive operating time to remove the top of the skull, considerable surgical morbidity as the scalp and skull are incised and subsequently must heal, significant post-operative pain to recover from the surgical wound, and extended time to complete recovery, because of the massive incision into the scalp and skull. Direct cost for medical care and indirect economic opportunity cost because of extended recovery time, and as a result extended absence from a working, productive lifestyle, are significant.
Another method to treat a pathological condition within the central nervous system is to apply radiation therapy. This method is normally used when the general condition of the patient will not permit surgery, when the disease is more diffuse and not localized in one small area, or when location of the disease is such that dissecting to it may cause considerable damage to normal or surrounding structures. Radiation therapy can attenuate diseased tissue, but does not remove the pathological substance, relying on normal body processes to remove the product of the radiation treatment. Although the "target" of radiation therapy can be focused to reduce effect on surrounding, normal tissue, some normal tissue is also destroyed. Radiation therapy has also caused a disease process, known as radionecrosis. Special equipment required to apply radiation therapy is very expensive, which adds to the overall cost of medical care, that is in turn expanding out of control in the country at the present time.
Lasers have been employed to ablate or evaporate pathological substances from the central nervous system, following the establishment of a pathway into the central nervous system to access the pathology and create "line of site" or line of laser energy transmission to the area of athe pathology. Although lasers can effectively evaporate small lesions, the process of debulking larger areas of lesion requires extended operating time, which adds to the cost of medical care and increases patient morbidity, a complication of general surgery. Lasers are very expensive and require special training for effective use, again adding to the cost of medical care.
Hand held instruments have been used to remove pathological substances form the central nervous system. These instruments are either inserted individually or in conjuction with a medical endoscope, through small holes in the head, during a less invasive surgical procedure. Although use of these instruments during this type of surgical technique reduces surgical morbidity, there are several drawbacks including extended operating time as the instruments, which must be very small, have to be constantly removed and cleaned and then reinserted to "bite off" additional chunks of the pathological substance, this process being repeated a significant number of times to remove even small lesions. This is a tedious process for the operating physician, and increases the duration if surgery. The alternative, to employ larger instruments which can bite off larger chunks of tissue at each insertion, dictates accompanying use of a larger instrument insertion cannula, which in turn mandates larger holes be placed onto the skull to accomodate these larger devices.
A search of patent classes 128, 604, and 623 identifies no existing patents which disclose a system of devices used to perform endoscopic removal of pathological tissue from the central nervous system, using an electromechanical cutting device or any other energy source, under continuous direct visual control, and incorporating continuous removal of debris created during the resecting procedure, while device components remain in their functional positions during the entire tissue removing process. However, related prior art for various components of the system described in this patent application include the following.
Prior art are various surgical devices which have been used mainly to remove pathological tissue from within body cavities such as the gastrointestinal system, urinary system, orthopaedic joints, etc. These are either single products, or a series of loosely related devices which are used during the operation but which are not coordinated to optimize their function and are not dependently controlled to produce an optimal effect. These devices include medical optical telescopes to view within a body cavity when used in conjunction with light illuminating products such as a fiber optic light bundle, energy form convertors and energy form transporters which use electrical, mechanical, laser etc. energy to cut, burn, or evaporate pathological tissue, suction devices which aspirate the cut pathological tissue from the body, and tubes used to transport the products of the tissue resecting process from the body cavity.
U.S. Pat No. 1,952,617 discloses an endoscope for viewing within the body during removal of a pathological substance from the genitourinary system. U.S. Pat No. 3,494,354 discloses a flexible endoscope for use in cancer diagnosis. Many additonal prior art devices, both rigid and flexible endoscopes, with the same generic design, have been manufactured to perform surgical procedures on various parts of the body. Although the optical and visualization characteristics of these devices are effective, their functions are not coordinated to other components of the system of products with which they are always used. In addition, these devices, being independently functioning, are not manufactured in a cost effective way, which increases their selling price. This in turn adds to the cost of medical care and the overall cost of health care, that is growing explosively out of control in the United States at the current time.
Various apparata in the surgical art, which remove undesired substances from various parts of the human or animal body, utilizing cutting elements, are disclosed in U.S. Pat Nos. 3,618,611; 3,732,858; 3,743,099; 3,844,272; 4,203,444; 4,274,414; 4,543,857; and 4,598,7120. Electromechanically powered , relatively low speed tissue resecting devices have been employed to perform orthopaedic arthroscopy of the knee, shoulder, wrist, and ankle. These devices have as component of their system, short, medium diameter, rigid cutting blades, or longer larger diameter rigid cutting blades which are inappropriate for use with and through the special design of the neuroendoscope.
Additional apparata in the surgical art which are used to inflow and aspirate fluids when used with endosocpes are disclosed in U.S. Pat. Nos. 3,850,162 and 3,900,022. Other prior art are peristaltic pumps used to inflow liquid into the body. Prior art is a device used to aspirate a liquid from the body. Prior art inflow and suction devices are not controlled and coordinated with each other, as each functions independently of the other.
Related prior art are machines which function independently, including light source illuminators, peristaltic pumps, pneumatically powered tissue resectors, suction machines, electromechanical tissue resectors used for surgical procedures other than indicated in this patent application, laser tissue resectors, electroablation tissue resectors, and ultrasonic energy tissue resectors. These devices are independently controlled. Their functions are not coordinataed with other devices with which they are always used. As a result, they are not manufactured in a cost effective manner and therefore their selling price is greater than a reasonable amount. This adds to the cost of direct medical care which is turn adds to the overall cost of health caare, that is increasing out of control in this country.
Prior art devices are not designed to coordinate functions identified in this invention, including illumination, visualization, electromechanical or other energy source cutting, and transport medium inflow and outflow, within the same operating console, and within the same device that is placed partially within the body. Therefore, these devices do not work as effectively together, extending operating time which also increases cost of medical care.